Stark effect modeling in the detailed opacity code SCO-RCG

9th International Conference on Inertial Fusion Sciences and Applications

Pain, J.-C.^1 ; Gilleron, F.^1 ; Gilles, D.^2

CEA, DAM, DIF, Arpajon

F-91297, France^1

CEA, DSM, IRFU, Gif-sur-Yvette

F-91191, France^2

关键词: Collision operators;    Hamiltonian matrix;    Microfield distribution;    Plasma environments;    Principal quantum numbers;    Satellite lines;    Semiempirical models;    Transition rates;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/717/1/012074/pdf
DOI  :  10.1088/1742-6596/717/1/012074

来源: IOP

【 摘 要 】

The broadening of lines by Stark effect is an important tool for inferring electron density and temperature in plasmas. Stark-effect calculations often rely on atomic data (transition rates, energy levels,...) not always exhaustive and/or valid for isolated atoms. We present a recent development in the detailed opacity code SCO-RCG for K-shell spectroscopy (hydrogen- and helium-like ions). This approach is adapted from the work of Gilles and Peyrusse. Neglecting non-diagonal terms in dipolar and collision operators, the line profile is expressed as a sum of Voigt functions associated to the Stark components. The formalism relies on the use of parabolic coordinates within SO(4) symmetry. The relativistic fine-structure of Lyman lines is included by diagonalizing the hamiltonian matrix associated to quantum states having the same principal quantum number n. The resulting code enables one to investigate plasma environment effects, the impact of the microfield distribution, the decoupling between electron and ion temperatures and the role of satellite lines (such as Li-like 1snn'' - 1s2n, Be-like, etc.). Comparisons with simpler and widely-used semi-empirical models are presented.